Dehydration: Causes, Symptoms and Risk Factors

Water is a key ingredient to important bodily functions, including joint lubrication, organ and tissue protection, waste removal, temperature regulation, and nutrient absorption.

Without enough water, the human body cannot perform as intended. This lack of water called dehydration, ranges from mild to severe. Know the causes and symptoms of dehydration, plus the steps you can take to ensure your body stays hydrated.

Causes of Dehydration

Dehydration occurs when you don’t drink enough water or fluids to replace the amount of fluid your body loses through sweat, urine, exhalation, bowel movements, and other processes. Certain conditions and activities can make you more prone. Below are some of the causes of dehydration.

• Diarrhea
• Vomiting
• Medication, such as diuretics, chemotherapy, and laxatives
• Illness
• Exercise
• Heat
• Increased urination from diuretics or conditions such as Addison disease
• Excess alcohol consumption
• Burns
• Kidney failure

Signs and Symptoms of Dehydration

The symptoms of severe dehydration can vary by age group, according to health experts.

Symptoms in Infants and Children

• Dry mouth
• Sunken eyes or cheeks
• Irritability
• Lethargy
• Lack of tears when crying
• Hours without wetting his or her diaper

Symptoms in Adults

• Dark-colored urine
• Strong urine odor
• Urinary infrequency
• Dizziness
• Lethargy
• Dry skin
• Lightheaded sensation
• Loss of sweat
• Thirst
• Headaches

As dehydration worsens, you may experience more severe symptoms. Troubling signs include faster breathing, an increased heart rate or heart palpitations, low blood pressure, fever, confusion, weakness, and extreme thirst or dry mouth.

With infants, the soft spot on top of the head may appear sunken. Another outward symptom is skin turgor, meaning if you pinch the skin on the back of your hand, it doesn’t immediately snap back into place. On children, test for skin turgor on the abdomen.

You may also experience cold or clammy skin as your body works to push more blood toward your vital organs. Without treatment, severe dehydration causes eventual death from organ failure.

Symptoms of Mild to Moderate Dehydration

• Bad breath
• Sugar cravings
• Cranky mood
• Difficulty concentrating
• Muscle cramps
• Constipation
• Decreased workout performance

Some of the symptoms aren’t so obvious for mild to moderate dehydration. Chronic dehydration increases the risk for other health conditions, such as kidney stones.

Who’s At Risk of Dehydration?

Children and the Elderly

Children and the elderly face the greatest risk of dehydration. Children lose more fluids than others when feverish, and older adults hold 15 percent less water than young adults.
Both populations may have additional risk factors, too, such as communication barriers and the inability to get water for themselves.

People with Certain Chronic Illnesses

Dehydration is a potential threat to people with certain chronic illnesses. The Mayo Clinic notes an increased risk for people with diabetes or kidney disease and those on diuretic medications.

People on fluid restriction for incontinence or heart failure are also at risk. Any time you become ill, especially with vomiting or diarrhea, you are more vulnerable due to the higher output of fluids while ingesting fewer foods and beverages.

Athletes Engaged in Strenuous Activities

Healthy adults may be at risk because of activity or environment. Athletes, for example, can become dehydrated from high-intensity training without proper fluid intake.
Outdoor workers are more susceptible to heat-related illnesses, like dehydration, when working in direct sunlight on hot days, according to OSHA. Taking precautions can help lower the risk.

Fluid Recommendations

Water needs vary by person. The Merck Manual recommends at least six glasses per day for adults. You may need to drink more if you spend time in hot weather or at high altitudes, if you are pregnant or breastfeeding, or if you exercise.

The American Council on Exercise advises you to drink at least 17 ounces of water two hours before physical activity, 10 ounces every 10 to 20 minutes during exercise, and more afterward.

The best fluid for hydration is water. While sports drinks may seem tempting, Harvard Health notes that sports drinks aren’t necessary for typical physical activity and may add undue calories and sugar to your diet.

Conversely, you may need beverages with electrolytes if you perform high-intensity activity for extended periods or sweat excessively, according to the American Council on Exercise.

An everyday rule of thumb is to drink water when you feel thirsty and monitor your urine color. Clear urine indicates too much water, which depletes your electrolytes, while amber or darker urine can indicate dehydration, according to UC San Diego Health.

Consult your doctor to discuss the right level of fluid intake for you. If you have a persistent illness and suspect that you may be dehydrated, or if you show symptoms of severe dehydration, seek immediate medical attention.